NYC-WTC_000195194

NYC 9/11 Public Portal Document

Water and ammonia-based cleaner (Windex®) did not smear. No difference in the cleanliness of the carpets based on use of water or soap and water was observed visually.

2.4 Cleaning Methods

Eleven tests were developed to evaluate eleven different cleaning methods that may have been used to clean residential and commercial spaces. To evaluate the equipment under comparable and varying conditions, tests were performed using similar equipment to clean areas that had both significant and minimal dust. Every attempt was made to evaluate each test on two spaces. An outline of the tests and prescribed cleaning methods follows:

Test 1 (A, B) A. Cleaning was conducted using residential quality upright vacuums and shop vacuums that are available from Hoover®, Eureka®, Ridgid® and Craftsman®, as well as wet wiping. B. Cleaning was conducted with the vacuums used in Test A, with the addition of an AFD, as well as wet wiping.

Test 2 (A, B) A. Cleaning was conducted in up to two units using HEPA-filtered upright vacuums and HEPA-filtered shop vacuums available from Hoover®, Eureka®, Ridgid®, and Craftsman®, as well as wet wiping. B Cleaning was conducted with the vacuums used in Test A, with the addition of an AFD, as well as wet wiping.

Test 3 (A, B) A. Cleaning was conducted in up to two units using commercial quality HEPA-filtered vacuums manufactured by Nilfisk™ Advance Vacuum Systems, as well as wet wiping. B. Cleaning was conducted in up to two units with the vacuums used in Test A, with the addition of an AFD, as well as wet wiping.

Test 4 (A, B ,C, D, E) A. Cleaning was conducted in commercial units and common areas using commercial quality HEPA-filtered vacuums manufactured by Nilfisk™ Advance Vacuum Systems*. An AFD was used. Debris that could not be vacuumed was manually removed and disposed. B. (Wet Wiping.) Additional cleaning of wall surface areas was conducted to remove any residues that may not have been removed by vacuuming. Wiping of the walls with a damp soapy cloth was performed to remove residual dust that may have adhered to the walls from the force of the collapse. Wet wiping of walls was performed in the Chiropractor’s Office, the Mattress Store, Unit 3C, and Unit 3B. C (Wet Vacuum.) Wall-to-wall carpeting was present in the Chiropractor’s Office, and the Mattress Store. The Chiropractor’s Office was wet-vacuumed using hot water; the Mattress Store was wet-vacuumed using hot water and carpet shampoo. D. (HVAC Cleaning.) HVAC systems are located in the Chiropractor's Office, the Mattress

*Test method 4A is the same as test method 3B. Both test methods use the same cleaning equipment. Test metliod 4A was used in commercial units; test method 3B was used in residential luiits.

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